As World AIDS Day dawns on December 1, the hope for a viable HIV vaccine gained new ground with Johnson & Johnson after the company announced a new study in Africa, launched by Janssen Pharmaceutical Companies with support from the National Institutes of Health and the Bill and Melinda Gates Foundation.
The first efficacy study for an investigational mosaic HIV-1 preventive vaccine, the trial (HVTN 705/HPX2008) will evaluate whether the investigational two-vaccine regimen is safe and able prevent HIV. Scientific American reports that the “mosaic technology” combines “immune-stimulating proteins from different HIV strains, representing different types of virus from around the world.”
“Our investigational vaccine is based on mosaic antigens that have been engineered using genes from a wide range of different HIV subtypes," reiterated Dr. Johan Van Hoof, managing director at Janssen Vaccines and Prevention, in a statement to the press. "The ultimate goal is to deliver a ‘global vaccine’ that could be deployed in any geographic region to help protect vulnerable populations at risk of infection.”
The vaccine trial is also known as “Imbokodo,” the Zulu word for the well-worn stones used for grinding grain, short-hand for a well-known proverb in South Africa: “Wathinta abafazi, wathinta imbokodo,” (roughly translated as: “You strike the woman, you strike the rock”). According to a Johnson & Johnson press release, the choice of the term pays homage “to the strength of women and their importance in the community.”
Avert, an organization fighting the global HIV epidemic, reports that as of 2015 on average 4,500 new HIV transmissions occur among young women every week, which is “double the number in young men” in east and southern Africa. Furthermore, the organization reports, in west and central Africa, 64 percent of new HIV infections among young people in 2015 were among women.
It is these kinds of numbers that have researchers focusing their vaccines on women. The Janssen trial hopes to recruit 2,600 women sexually-active women aged 18-35 in five sub-Saharan Africa countries. Another vaccine trial (HPTN 077), by ViiV Healthcare, is already underway, enrolling 3,200 women in the region to evaluate using a long-acting injectable version of cabotegravir as a vaccine, reports NAM's AIDSMap.
Janssen’s own proof-of-concept efficacy study follows two earlier clinical trials including the ongoing TRAVERSE study, which compares two regimens containing adenovirus 26 (Ad26) vectored vaccines. Plus previously reported that Ad26 (a vaccine that has parts of HIV in it to spur the immune system to fight HIV) was shown effective in suppressing viral loads in HIV-positive monkeys — even after treatment was discontinued. It could therefore eventually lead to a functional cure for HIV.
In this study, Ad26 will be combined with a protein, Clade C gp140, which (according to the study’s site, Imbokodo.org.za) is similar to a protein found on the surface of HIV, and also helps humans develop an immune response to the virus. In addition, the protein will be mixed with the booster Aluminum Phosphate (which is also used in vaccines for hepatitis A and tetanus).
Results could take up to four years, researchers stated on the site. Still, as Johnson & Johnson’s press materials point out, for the first time in over a decade, two vaccine trials are ongoing at the same time. Both are raising new hope for a long-acting HIV prevention for women — and men — in Africa and beyond.
“Developing a vaccine against HIV is a top priority and our best hope for a world without AIDS," noted Dr. Paul Stoffels, chief scientific officer, Johnson & Johnson, in a company press release. "Finding an effective HIV vaccine to protect people at risk has been a major scientific challenge, but today there is new optimism that we can get there.”